of london



H. C. BINGHAM. ROTARY FURNACE FOR ROASTlNG-BLENDE, PYRITES, 0R OTHERVMINERALS.

APPLICATION FILED MAR. 25. I919.

1,3223223. Patented Nov. 18,1919.

INVENTOR IWW UNITED STATES PATENT OFFICE.

HENRY CHARLES BIN GI-IAM, OF LONDON, ENGLAND, ASSIGNOR TO HUNTINGTON, HEBERLEIN AND COMPANY, LIMITED, 0]? LONDON, ENGLAND.

ROTARY FURNACE FOR ROASTING BLENDE, PYRITES, OR OTHER MINERALS.

Specification of Letters Patent.

Patented NOV. 18, 1919.

Application filed March 25, 1919. Serial No. 285,071.

To all whom it may concern:

Be it known that I, HENRY CHARLES BING- HAM, a subject of the King of Great Britain and Ireland, residing at 7 Gracechurch street, in the city of London, England, have invented new and useful Improvements in Rotary Furnaces for Roasting Blende, Pyrites, or other Minerals, of which the following is a specification.

This invention relates to improvements in roasting furnaces of the type wherein the ores, concentrates or the like, are exposed 011 circular hearths arranged one above another and over which arms, extending radially from a central and slowly rotating shaft and carrying rabbles, are caused to travel with the object of stirring the material under treatment and gradually sweeping it from each hearth to that next below. Hitherto these circular hearths have been arranged either horizontally or at a slight inclination downward and outward. In the latter case, the material lying upon each alternative hearth is swept radially by the rabbles in opposite directions, and flows over one hearth in the direction of its inclination, and over the next hearth in succession in a direction opposed to its inclination.

In treating certain kinds of ore, such for example as blende, I have found that the flow of the material, especially over a downwardly inclined hearth, is too free; being, to some extent, independent of the action of the rabbles. My invention is directed to resisting this natural fluency; and with this object, I incline the several hearths alternately in opposite directions, so that the radial How of the material under the influence of the rabbles is constantly opposed by the inclination of the hearth over which it is caused to travel.

A rotary furnace constructed in this manner is represented in vertical section in the accompanying drawing. Inclosed within a chamber 0 are circular hearths a which surround a slowly rotating shaft 1). To the latter are attached radial arms d furnished as to their under side with rabbles d which gradually sweep the material in a radial direction alternately outward and inward as regards each successive hearth. The upper surface of each hearth is inclined in a direction opposed to that of the movement of the material; and the angle of such inclination may be varied to suit materials possessing difierent degrees of nobility. The angle of inclination may also be varied as between one hearth and another.

Under conditions such as above described, the flow of the material independently of the action of the rabbles is prevented, a more equable roasting 0f the material is obtained and a more perfect elimination of the sulfur effected.

I claim A rotary furnace for roasting blende, pyrites or other minerals, wherein all the hearths are arranged at an inclination opposed to that of the radial movement of the material under treatment, substantially as and for the purpose set forth.

HENRY CHARLES BIN GHAM. 

